1. Field of the Invention
The present invention relates to a copying apparatus and an operating method therefor and, more particularly, to a copying apparatus and an operating method therefor in which images of an original are copied on a sheet of copy paper and additional information such as date or page number can be entered on the same sheet.
2. Description of the Related Art
A copying apparatus capable of recording additional information such as date and page number on a sheet of copy paper as well as images of an original is disclosed in Japanese Patent Publication No. 59-52811/1984.
In the copying apparatus disclosed in the above mentioned publication, images of an original are scanned and exposed to be projected on a photoreceptor and first latent electrostatic images corresponding to the original images are formed on the photoreceptor. When the first latent electrostatic images are formed on the photoreceptor, a portion of the optical path projecting the images of the original is partially intercepted, in order to reserve charges on that area of the photoreceptor on which the additional information is to be entered. Second latent electrostatic images corresponding to the additional information are formed by means of a liquid crystal head on that area on which the charges are reserved, and thereafter the first and second latent electrostatic images are developed simultaneously by one developing unit.
However, in the copying apparatus disclosed in the above mentioned publication, the images of the original and the additional information can be formed on the sheet of paper in only one color. Namely, the images of the original cannot be formed in a color different from that of the additional information.